CN101420675B

CN101420675B - Fee counting method, anchor point on session control signaling surface

Info

Publication number: CN101420675B
Application number: CN 200710167315
Authority: CN
Inventors: 张朝辉; 解晓强
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2007-10-22
Filing date: 2007-10-22
Publication date: 2010-11-10
Anticipated expiration: 2027-10-22
Also published as: WO2009052766A1; CN101420675A

Abstract

The invention discloses a charging method of multimedia service continuity. The charging method comprises the following steps: receiving a switching request for switching multimedia services from a source terminal UE-S to a target terminal UE-T; determining a charging object, and carrying out charging control on a new access object according to the determined charging object which is a source terminal user or a target terminal user. The invention further discloses a session control signaling plane anchor point. The anchor point comprises a receiving module which receives a switching request from a switching initiator, and transmits the received switching request to a charging control module, wherein, the switching request comprises the information about switching the multimedia services from the UE-S to the UE-T; the charging control module which receives the switching request, determines the charging object, and carries out the charging control on a new access object according to theUE-S information and the UE-T information in the determined charging object and the switching request. The invention also discloses a media gateway control entity.

Description

Charging method and session control signaling plane anchor point

Technical Field

The present invention relates to the technical field of multimedia service continuity, and in particular, to a charging method for multimedia service continuity and a session control signaling plane anchor point.

Background

Voice Call Continuity (Voice Call Continuity VCC) is a service provided in an IMS network to which a user belongs, and enables a bidirectional handover of a Voice Call of a user between a circuit domain (CS domain) and the IMS network. The converged IMS architecture enables seamless voice call service to be realized under a CS domain and an IP connection access network (IP-CAN).

When a VCC User Equipment (User Equipment UE) is engaged in an active voice session, call continuity can be achieved by initiating a domain switching procedure. In order to perform domain switching, a call originated or received by a VCC subscriber is anchored to a domain switching processing entity dtf (domain transfer function) of the IMS network to which the subscriber belongs. The DTF is an application server with B2BUA functionality. In VCC, a voice session control leg between a DTF and a VCC UE is called an access leg (access leg), and a voice session control leg between the DTF and a remote user is called a remote leg (remote leg). The handover is to replace the old access leg in the hand-out network connected to the remote leg with the new access leg in the hand-in network. When the far-end user's equipment supports IMS, its bearer connection is replaced end-to-end. When the remote user equipment supports CS/Public Switched Telephone Network (PSTN), the bearer connection is replaced between VCCUE and MGW (media gateway function). When the new access leg is fully established, the VCC UE switches the media input output channel from the hand-out domain to the hand-in domain.

The concrete realization of the scheme is as follows: when the user's VCC ue detects a need to switch from the source network to the destination network, a special number is called in the destination network to establish a new access leg, i.e., a new voice session is established between the DTF and the VCC ue in the hand-in network. Through which the call request may arrive at a DTF process, from which the DTF may determine that it is a domain switch request. Media components of the remote leg are redirected to the new access leg according to media information supported by the VCC user equipment in the newly established call and renegotiation media between the remote user equipment of the original call, namely, the remote leg is updated to replace the access leg. After the media negotiation and the new call establishment are completed, the DTF or the VCC ue releases the call in the handover source network, i.e., releases the old access leg, and releases the session between the original DTF and the VCC ue in the handover-out network. This completes the replacement of both access legs so that the user's voice call is handed over to the destination network. The voice call of the user is kept uninterrupted in the switching process, and the service experience of the user is improved.

With the evolution of 3GPP technology, the requirements for continuity of multimedia services are increasing, and these requirements include moving multimedia sessions or media components on one terminal between different terminals under the control of a user or a network, i.e. performing handover of multimedia sessions or media components. In 3GPP, application scenarios providing multimedia call continuity (MMSC) have been discussed, which range from switching one multimedia session between networks of different access technologies, and from switching certain media components, i.e. media components, in one multimedia session to several destination terminals under user control or vice versa.

The inventor finds out in the invention process that: at present, only application scenes are provided for the continuity processing of the multimedia service, and no specific implementation scheme is provided, and no specific implementation scheme for charging in the continuity processing process of the multimedia service is provided.

Disclosure of Invention

The embodiment of the invention provides a charging method for multimedia service continuity and a session control signaling plane anchor point, which can solve the problem of realizing charging in continuous multimedia service.

The charging method for multimedia service continuity provided by the embodiment of the invention comprises the following steps:

receiving a switching request for switching a multimedia service from source end user equipment UE-S to destination end user equipment UE-T;

determining a charging object;

when the charging object is a source end user, the network at the UE-S side performs charging control on a new access leg; sending an indication to the UE-T side network that the new access leg is free; the UE-T side network receives the indication and controls the new access leg free of charge;

when the charging object is a destination end user, the UE-T side network carries out charging control on a new access leg; the network at the UE-S side controls the new access leg free of charge;

the new access leg is established in the multimedia service switching.

The anchor point of the session control signaling plane provided by the embodiment of the invention comprises:

the receiving module receives a switching request from a switching initiator and transmits the received switching request to the charging control module, wherein the switching request comprises information for switching the multimedia service from the UE-S to the UE-T;

the policy acquisition module stores the operator policy or interacts with other equipment on the network side to acquire the operator policy and sends the stored or acquired operator policy to the charging control module;

a charging control module for receiving the switching request, determining a charging object, and performing charging control on a new access leg established in the multimedia service switching according to the determined charging object, wherein the charging control module comprises:

the charging object determining module receives the operator strategy from the strategy acquiring module, determines a charging object according to the operator strategy and informs the charging executing module and the free executing module of the determined charging object;

the charging execution module is used for interacting with a charging entity of the source end user according to the received notice that the charging object is the source end user, and charging the source end user for a new access leg established in the multimedia service switching;

the free execution module is used for sending a free instruction to the UE-T network side according to the notice that the received charging object is the source end user; and according to the received notice that the charging object is the destination end user, the charging is not initiated to the charging entity of the source end user, or the charging object interacts with the charging entity of the source end user, and the new access leg established in the multimedia service switching carries out free control on the source end user.

In the embodiment of the invention, when the method is applied to the process of realizing the continuity of the multimedia service, after receiving a switching request for switching a multimedia session or a media component to a destination terminal, a session control signaling plane Anchor point S-Anchor determines a charging object as a source terminal or a destination terminal according to the switching request, and correspondingly performs charging control, thereby solving the problem of realizing the switching charging in the continuous multimedia service.

Drawings

Fig. 1 is a block diagram of a multimedia service continuity process according to the present invention;

fig. 2 is a flow chart of the multimedia service handover under the framework of fig. 1;

FIG. 3 is a schematic diagram illustrating a session control signaling plane anchor according to an embodiment of the present invention;

FIG. 3a is a schematic diagram of another embodiment of a session control signaling plane anchor point according to the present invention;

FIG. 3b is a schematic diagram of another embodiment of a session control signaling plane anchor point according to the present invention;

fig. 4 is a schematic diagram illustrating a configuration of a media gateway control entity according to an embodiment of the present invention;

FIG. 5 is a flowchart of a charging method for continuous multimedia services according to a first embodiment of the present invention;

fig. 6 is a flowchart of a charging method for continuous multimedia services according to a second embodiment of the present invention;

fig. 7 is an exemplary flowchart of the charging method for continuous multimedia services of the present invention, where the destination is in the CS domain;

fig. 8 is a flowchart of a charging method for continuous multimedia services according to a third embodiment of the present invention;

fig. 9 is a flowchart of a charging method for continuous multimedia services according to a fourth embodiment of the present invention;

fig. 10 is a flowchart of a fifth embodiment of a charging method for continuous multimedia services according to the present invention;

fig. 11 is a flowchart of a charging method for continuous multimedia services according to a sixth embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention are described in further detail below with reference to the accompanying drawings.

In the specific implementation scheme of the multimedia service continuity processing and the implementation scheme of the charging in the process of realizing the multimedia service continuity processing, the invention focuses on the implementation of the charging scheme in the process of the service continuity processing in the multimedia session.

The implementation scheme for implementing the multimedia service continuity process is illustrated by the following fig. 1 and fig. 2.

Fig. 1 is a block diagram illustrating a multimedia service continuity process. In fig. 1, solid lines indicate control plane connections and dashed lines indicate user plane connections. The multimedia service continuity processing is realized by switching, wherein, a switching initiator can be a switching source terminal (UE-S), a switching destination terminal (UE-T), a third party associated with the UE-S or the UE-T or a switching initiator entity (HOCF) in a network.

The switching source end is an entity where the multimedia service is located before switching; the switching destination end is a destination entity of the multimedia service switching. A switching source end belongs to a source end user device, and similarly, a switching destination end belongs to a destination end user device. A remote handover (UE-R) is a remote entity that communicates with the UE-S. The handover source subscriber and the handover destination subscriber corresponding to the handover source and the handover destination may be identified by, but not limited to, an IMS public subscriber identity in an IMS domain, and may be embodied as, but not limited to, a mobile subscriber international ISDN number (MSISDN) in a CS domain. The multimedia service handover comprises at least one media component handover.

As can be seen from fig. 1, before handover, UE-S and UE-R perform service transmission of a multimedia session in the user plane; in the signaling plane, the signaling of the UE-S is anchored to the S-Anchor to which the UE-S belongs, and is denoted as S-Anchor (UE-S), the connection established between the S-Anchor (UE-S) and the UE-S is an old access leg, and the connection established between the S-Anchor (UE-S) and the UE-R is a far-end leg. After switching, the session or media component on the UE-S is switched to the UE-T, so that the UE-T and the UE-R carry out the service transmission of the multimedia session on the user plane; in a signaling plane, an S-Anchor (UE-S) is connected with a remote leg through a new access leg established in switching between the S-Anchor (UE-T) and the UE-T for signaling transmission. Wherein, S-Anchor (UE-T) is the signaling plane Anchor point of UE-T. In the signaling plane connection after the handover, the S-Anchor (UE-T) may not appear, and then a new access leg is directly established between the S-Anchor (UE-S) and the UE-T, for example, the S-Anchor (UE-T) may not appear in the signaling plane when the target end user does not subscribe to the multimedia service continuity.

The S-Anchor may appear AS an Application Server (AS) in the IMS network.

The switched multimedia service may be all media components in the session (indicated by the session S1), or may be a part of the media components in the session (indicated by the part of the media component F1), where the part of the media components may be one media component in the session or may include several media components in the session. When the switched multimedia service is all the media components in one session, the multimedia service can be switched into a new session, namely after the switching is successful, the switched multimedia service is still all the media components in the new session; the multimedia service can also be switched into the existing session, and after the switching is successful, the switched multimedia service is used as a new media component in the existing session. Similarly, when the switched multimedia service is a part of media components, the multimedia service can be switched into a new session, that is, after the switching is successful, the switched multimedia service is all the media components in the new session; the multimedia service can also be switched into the existing session, and after the switching is successful, the switched multimedia service is used as a new media component in the existing session.

In addition, the new access leg established in the handover is a signaling connection between the S-Anchor (UE-S) and the UE-T. If the multimedia service is switched into a new session, namely all media components in the new session are obtained after the multimedia service is switched, the signaling connection is associated and controls the session signaling connection of all the media components in the new session; if the multimedia service is switched into the existing session, i.e. the multimedia service is switched into a part of media components in the existing session, the signaling connection is established in the session signaling connection of the existing session, and the signaling connection of the switched-in new media components is associated and controlled.

In fig. 1, UE-T and UE-S may be the same terminal of the same user of the same network, different terminals of different users of the same network, or different terminals of different networks. The above-described relationship between the third party initiating the handover and the UE-S is similar to the UE-T and UE-S relationships referred to herein.

The same network may be a network of the same operator, e.g. an IMS network; the user refers to an individual, which can be a person or an organization, etc.; the same user can be associated with one IMPU, multiple IMPUs or both the IMPU of the IMS domain and the MSISDN of the CS domain in the IMS network; the terminal may be a single mode terminal or a multimode terminal, such as a WLAN and 2G CS access mode terminal.

In addition, UE-T and UE-S may be IMS terminals or CS terminals. Similarly, the UE-R can also be a CS terminal or an IMS terminal, if the UE-R is a CS terminal, MGCF exists in the signaling plane between the S-Anchor (UE-S) and the UE-R, and MGW related to the MGCF also exists in the user plane.

In the network entity shown in fig. 1, the S-Anchor (UE-S) and the S-Anchor (UE-T) may be different entities or the same entity. If the two entities are the same entity, the two entities can communicate through an internal interface and can also share data, including user data of UE-S and UE-T; if the entities are different entities, SIP signaling interaction is used. For convenience of description in the figure, S-Anchor is written as S-A in the figure.

Fig. 2 shows a multimedia service handover procedure based on the framework shown in fig. 1, in which after the UE-S establishes a session S1 with the UE-R via the S-Anchor (UE-S) (S1 includes a media component F1), the following steps are included:

step 1, the handover initiator generates a handover request for switching the multimedia service, which may be a session S1 (i.e. all media components in S1) or a part of media components F1 in S1, to the UE-T according to the handover trigger condition, and sends the handover request to the S-Anchor (UE-S) using SIP signaling or via CS network signaling. Where media component F1 may be one or more media components.

In this step, the handover initiator may be UE-S, UE-T, HOCF or a third party UE.

And step 2, the S-Anchor (UE-S) performs service control according to the received switching request.

And step 3, negotiating with the UE-T by the S-Anchor (UE-S) to establish a new access leg.

Step 4, S-Anchor (UE-S) media negotiations with UE-R to switch session S1 or media component F1 to UE-T so that UE-T can communicate with UE-R through the new access leg, S-Anchor (UE-S) and negotiations with UE-S process session S1, wherein the process of S1 may be to release S1 or delete media component F1 in S1, or simply copy session S1 or media component F1 to UE-T so that UE-S can continue to communicate with UE-R.

The following describes the charging scheme provided by the present invention, the session control signaling plane anchor point for charging control related in the charging scheme, and the specific implementation of the media gateway control entity for performing charging information conversion in the charging process in detail.

In the following embodiments, the IMS is described as an example. Wherein IMS is a description of 3GPP, and a similar multimedia subsystem called multimedia domain (MMD) also exists in 3GPP 2; for simplicity of description in the present invention, only IMS is described, but it is obvious that the described method is also applicable to MMD systems. The method is also applicable to the IMS system defined by TISPAN.

In addition, the entity related to the UE-S side network or UE-T side network charging, which is not described in the following embodiments, also performs the charging operation according to the charging method in the corresponding embodiment during the handover process.

As for the session control signaling plane anchor point for implementing the above charging scheme provided by the present invention, the embodiment thereof is as shown in fig. 3, and includes a receiving module and a charging control module. Wherein:

the receiving module receives a switching request from a switching initiator for switching the multimedia service from the UE-S to the UE-T and transmits the switching request to the charging control module.

And the charging control module determines a charging object and performs charging control on a new access leg established in the multimedia service switching according to the determined charging object.

As shown in fig. 3a, in this embodiment, the session control signaling plane anchor point may further include: the policy acquisition module stores the operator policy or interacts with other equipment on the network side, acquires the operator policy and sends the stored or acquired operator policy to the charging control module; the charging control module determines a charging object according to the sent operator policy.

As shown in fig. 3b, in this embodiment, the charging control module may include: the system comprises a charging object determining module, a charging execution module and a free execution module; wherein:

the charging object determining module receives the operator strategy from the strategy obtaining module, determines the charging object according to the operator strategy and the information in the switching request, namely determines the charging object to be the switching source end user or the switching destination end user, and then informs the charging executing module and the free executing module of the determined charging object.

The charging execution module is interacted with a charging entity of the source end user according to the received notice that the charging object is the source end user, and charges the source end user for a new access leg established in the multimedia service switching;

the free execution module sends a free instruction to the UE-T network side according to the received notice that the charging object is the source end user; and interacting with the charging entity of the source end user according to the received notice that the charging object is the destination end user, performing free control on the source end user according to the switched multimedia service, and terminating the charging on the old access leg for the source end user.

If the source end user is an online charging user, the charging execution module interacts with the charging entity, and charging the source end user for the switched multimedia service specifically comprises the steps that the charging execution module sends a Credit Control Request (CCR) about a new access leg to an Online Charging System (OCS) (UE-S) of the source end user, wherein the credit control request can be embodied as a Reserve Unit request (Reserve Unit request), and the charging execution module performs credit control on the source end user according to the response of the CCR; the free execution module interacts with a charging entity of a source end user, and the free control of the source end user is carried out on the switched multimedia service, wherein the charging execution module sends CCR (charging free indication) to an OCS (UE-S) for a new access leg, the OCS (UE-S) does not charge the source end user for the new access leg according to the free indication in the CCR, or the free execution module returns the obtained charging relevant resource after sending a credit control request to the OCS (UE-S) to obtain the charging relevant resource of the new access leg; or the free execution module does not perform charging information interaction with an OCS (UE-S) on the new access leg, so that the new access leg can perform free operation on the UE-S user.

If the source end user is an offline charging user, the charging execution module interacts with the charging entity, and charging for the source end user on the switched multimedia service specifically comprises the steps that the charging execution module sends A Charging Request (ACR) to a charging data function entity CDF (UE-S) of the source end user, wherein the ACR comprises charging information related to a new access leg, and the CDF (UE-S) generates a CDR for the source end user according to the ACR and returns a response; and the free execution module interacts with a charging entity of the source end user, and the free control of the source end user is carried out on the switched multimedia service, wherein the free execution module sends ACR (access control record) including free indication to a CDF (UE-S) according to the new access leg, and the CDF (UE-S) generates CDR including the free indication according to the free indication in the ACR, so that the source end user is not charged according to the new access leg.

Fig. 4 is a schematic structural diagram of a specific embodiment of a media gateway control entity provided in the present invention. The media network management control entity shown in fig. 4 is arranged at a connection point between the IMS domain and the CS domain, and serves as a gateway between the IMS domain and the CS domain. As shown in fig. 4, in this embodiment, the media gateway control entity includes: the device comprises a receiving module, a charging related information conversion module and a sending module. Wherein:

and the receiving module receives the charging relevant information related to the switched multimedia service from the IMS domain and transmits the charging relevant information to the charging relevant information conversion module.

The charging relevant information conversion module converts the charging relevant information in the IMS domain format into the charging relevant information in the CS domain, and transmits the converted charging relevant information to the sending module;

and the sending module is used for sending the received converted charging related information to the CS domain.

The charging related information includes: a free indication, an associated charging identifier, or an initial direction of the switched multimedia service. Here, the initial direction of the switched multimedia service may be an initial establishment direction of a switched session, such as whether the UE-S is a calling party or a called party, or an initial initiation establishment direction of a switched media component, such as whether the UE-S initiates establishment or UE-R initiates establishment.

The following is a detailed description of a specific embodiment of the charging method of the present invention.

In the following embodiments some IMS/CS network entities are omitted, only the relevant parts are shown, where the S-Anchor may be embodied as an application server in the IMS domain.

In the first embodiment of the method of the present invention, a N2C (Network to Client) manner is adopted for switching, that is, the establishment of a new access leg at a destination is initiated from an S-Anchor (UE-S) on a Network side, which is embodied as an application server in an IMS domain, and a source end user is taken as an example, a flow of the embodiment is shown in fig. 5, and specifically includes the following steps:

step 1, UE-S has established session S1 with UE-R through S-Anchor (UE-S) by using SIP signaling or via CS network signaling, S1 contains media component F1, S-Anchor (UE-S) receives handover request of handover initiator, requests multimedia service, such as all media components in session S1 or part of media component F1 in S1 to be handed over to UE-T, wherein the handover initiator can be UE-S, UE-T, third party user equipment or HOCF, and sends to S-Anchor (UE-S) through SIP signaling or via CS network signaling.

The media component F1 in this step may include one media component or may include a plurality of media components.

In step 2, S-Anchor (UE-S) performs switching control on the received switching request, determines that the switching only charges a source end user, determines that the charging type of the source end user is an offline charging type, sets a destination end user free indication in a generated session establishment request (INVITE) aiming at UE-T, and sends the session establishment request, wherein the session establishment request is routed to S-Anchor (UE-T) according to an IMS session establishment mode, so that the destination end user is controlled freely by a new access leg through the session establishment request.

The determination of whether the source terminal or the destination terminal is charged by the handover may be specifically determined according to an operator policy, and then a specific charging object may be determined by combining UE-S information and UE-T information in the handover request, that is, the charging object is determined as a source terminal user or a destination terminal user in the handover. The specific content of the operator policy may be charging only for the source, or may also be content in the handover request, where the operator policy may be set in the S-Anchor (UE-S), or may be obtained by interacting with other entities. For example, the operator policy determines the initiator as the charging object according to the initiator information included in the handover request or in combination with the initiator, the source and/or the destination. The manner of determining that the charging object is the destination or the second destination in the other embodiments described below is the same as in this embodiment, and will not be described again below.

In the INVITE sent in step 3, the destination-end user free indication may be carried by a session initiation protocol P Charging Vector (SIP P-Charging-Vector) header field in the request, may be carried by newly defining an SIP header field or parameter, may be carried by using an original header field or parameter for extension, or may be carried by using message content of a Session Description Protocol (SDP).

Step 4, S-Anchor (UE-T) carries on the switch control, include setting up the request to judge the request is the multimedia service switching request according to the conversation received, namely insert leg set up the request newly, and instruct according to the free of charge of end user of the purpose, determine not to trigger the online charging request to the end user of online charging, then in step 5, establish the request to route the conversation to UE-T according to IMS conversation and set up the way.

In step 4, the purpose end user is not charged, except that the purpose end user is not triggered to have an online charging request, the following two ways can be realized:

the first is that, based on the destination-end user free indication, the S-Anchor (UE-T) includes the relevant information of the destination-end user free indication in the CCR request sent to the OCS (UE-T), and the OCS (UE-T) may generate a corresponding record according to the online charging policy based on the relevant information, but does not actually deduct the balance of the destination-end user account.

Secondly, the S-Anchor (UE-T) obtains charging related resources from the OCS (UE-T) according to the free indication of the destination user and a normal processing mode, and returns the charging related resources obtained from the OCS (UE-T) to the OCS when the established new access leg is released, thereby realizing that the destination user is not charged.

And step 6-8, through the middle negotiation process between the S-Anchor (UE-S) and the UE-T, the UE-T sends the 200OK sent to the S-Anchor (UE-S) through the S-Anchor (UE-T), and the establishment of a new access leg is completed.

Step 9-12, S-Anchor (UE-S) sends charging request (ACR) to CDF (UE-S), and requests to start charging for new access leg; and a Charging Data Function (CDF) (UE-S) generates a corresponding CDR according to the received request and charges the new access leg. And simultaneously, the S-Anchor (UE-S) respectively sends ACR requests related to the old access leg and the far-end leg to the CDF (UE-S), the ACR requests indicate that Charging of the old access leg or the cut-out media component is stopped and Charging of the far-end leg is updated, and the CDF (UE-S) updates a corresponding Charging Data Record (CDR) according to the ACR requests. If the charging is stopped for the old access leg, the ACR is used to stop the charging request, and other charging requests are updated.

Here, if the same charging session is associated with the new access leg, the old access leg and the remote leg, the S-Anchor (UE-S) may send only one ACR update charging request to the CDF (UE-S) indicating to stop charging the old access leg or the switched media component and update charging of the remote leg, and to charge the new access leg.

After step 12, processing of other procedures for handover is performed.

Through the above-mentioned flow, in the process that the switched session S1 or the media component F1 is switched to the UE-T, and during the whole period existing after being switched to the UE-T, the source user charging system generates and maintains a complete charging history record, thereby implementing charging to the source user with respect to the new access leg.

In this embodiment, the charging processing may further be performed on the handover event, and the specific implementation is as follows: in the flow of the above embodiment, after receiving a handover request from a handover initiator, an S-Anchor (UE-S) sends a handover response to the handover initiator, and simultaneously sends an ACR charging request to a CDF (UE-S), where the request may be an event type, and the CDF (UE-S) charges a handover event according to the ACR charging request, generates a corresponding CDR, and returns a response to the S-Anchor (UE-S). In other embodiments described below, when the source end user performs offline charging, the charging processing may also be performed on the handover event, and the specific implementation is the same as that in this embodiment, which will not be described again below.

In the above process, the source end user is determined to be an offline charging user in step 2, and charging control of the source end user is described, if the source end user is determined to be an online charging user in step 2, a CCR request is sent to an OCS (UE-S) of the source end user for a session or a media component to be switched, and an available charging related resource is obtained, so that the OCS (UE-S) is controlled to charge the source end user. In sending the CCR request to the OCS (UE-S), information for starting charging for the new access leg, information for stopping charging for the old access leg or the cut-out media component, and information for updating charging for the remote leg may be included at the same time; or, in sending the CCR request to the OCS (UE-S), only the information for starting charging for the new access leg may be included, then the S-Anchor (UE-S) further sends to the OCS (UE-S) a CCR including a request for stopping charging for the old access leg or the cut-out media component and a CCR including a request for updating charging for the remote leg; the OCS (UE-S) may start charging for the new access leg while updating the charging for the remote leg and stop charging for the old access leg or the cut-out media component.

Optionally, in step 8, after the S-Anchor (UE-S) receives the 200OK handover success, the obtained available charging related resources may be updated to the OCS (UE-S), and when negotiating with the UE-R and the UE-S, interact with the OCS (UE-S) to control the OCS (UE-S) to stop charging the source user for the old access leg or cut-out media component, and update charging for the source user for the remote leg.

In this embodiment, after receiving a handover request from a handover initiator, the S-Anchor (UE-S) may send a CCR charging request to the OCS (UE-S) to charge for a handover event. In other embodiments described below, when the source end user is an online charging user, as in this embodiment, the source end user may be charged for the handover event, and the specific implementation is the same as in this embodiment, and will not be described again below.

According to the initial establishment direction of the handover session (whether the UE-S is a calling party or a called party) or the initial initiation direction of the handed over media (whether the UE-S is initiated or the UE-R is initiated), an identifier for charging according to the initial establishment direction or the initial initiation direction may be set in the ACR or CCR sent by the S-Anchor (UE-S).

The ACR or CCR sent by the S-Anchor (UE-S) may include charging association information, where the charging association information may be a special charging identifier, and may be carried in Service Specific Data or Service-Context-Id AVP in the CCR request, for example; this special charging identity is also included in the corresponding charging record generated by the CDF (UE-S) or OCS (UE-S). When the new, old and far-end legs use the same charging Session (Diameter Accounting Session) to implement charging, the charging association information may also be a Session identifier (Session ID) of the charging Session (Diameter Accounting Session) associated with the new, old and far-end legs.

In this embodiment and the following embodiments, the S-Anchor (UE-S) and the S-Anchor (UE-T) may be in different entities or may be in the same entity. When both are in the same entity, both can communicate through the internal interface and can also share data, including sharing user data for UE-S and UE-T.

The flow of the second embodiment of the method of the present invention is shown in fig. 6, and comprises a media component F1 in S1, S1 when a session with UE-R has been established by UE-S through S-Anchor (UE-S) using SIP signaling or CS network signaling, and thereafter, the method comprises the following steps:

step 1-2, UE-T initiates a switching request in a session establishment mode according to user indication, preset strategy or receiving a switching request of UE-S, a third party or an HOCF, and requests to switch S1 or F1 to the UE-T. The request reaches the S-Anchor (UE-T) along the session establishment path, and the S-Anchor (UE-T) performs related service control including performing signaling anchoring, etc.

And 3-4, the S-Anchor (UE-T) routes the switching request to the S-Anchor (UE-S) according to an IMS session establishment mode, sends CCR to the OCS (UE-T) of the destination terminal user and carries out charging interaction with the OCS (UE-T).

And 5-7, after receiving the switching request, executing switching control by the S-Anchor (UE-S), and determining that a charging object is a source end user, sending CCR for starting charging of a new access leg to the OCS (UE-S), wherein the OCS (UE-S) performs credit control on the source end user according to the request and returns available charging related resources. The CCR results in a charging session being established to charge for the new access leg established by the handover. In addition, the S-Anchor (UE-S) also sends CCR requests to the OCS (UE-S) relating to the old access leg and the remote leg, respectively, indicating that charging for the old access leg or the switched-out media component is stopped and the charging for the remote leg is updated. If the charging is stopped for the old access leg, the charging request is stopped by using the CCR, and other charging requests are updated.

In steps 5 to 7, if the charging session associated with the new, old and remote legs is the same, the S-Anchor (UE-S) may send only one CCR update charging request to the OCS (UE-S), and at the same time instruct to stop charging for the old access leg or the switched-out media, update charging for the remote leg, and charge for the new access leg.

Similarly to the first embodiment, the CCR sent by the S-Anchor (UE-S) may include charging association information, where the charging association information may be a special charging identifier, for example, the charging association information may be carried in Service Specific Data or Service-Context-Id AVP in the CCR request, and then the corresponding charging record generated by the OCS (UE-S) also includes the special charging identifier; when the new, old and far-end legs use the same charging Session (Diameter Accounting Session) to implement charging, the charging association information may also be a Session identifier (Session ID) of the charging Session (Diameter Accounting Session) associated with the new, old and far-end legs.

Intermediate to the handover performed in step 8, comprising: negotiation with the UE-R, negotiation with the UE-S at the time of source end processing, optionally, in step 9-11, similar to step 5-7, the S-Anchor (UE-S) sends a CCR request to the OCS (UE-S), updates available charging related resources, and the OCS (UE-S) performs corresponding credit control.

In step 12, the S-Anchor (UE-S) returns a 200OK session establishment success response to the S-Anchor (UE-T) in the IMS session establishment mode, where the response includes a destination end user free indication. The destination user free indication can also be transmitted to the UE-T network by the S-Anchor (UE-S) in the handover middle procedure of step 8, for example, the response in the course of 183 session.

Step 13, the S-Anchor (UE-T) decides not to charge the destination user according to the received destination user free indication, and then in step 14, sends a CCR request with the free indication to the OCS (UE-T), so that the OCS (UE-T) sets a corresponding free indication in the generated charging record according to the free indication in the received CCR request, thereby implementing not to charge the destination user; alternatively, instead of sending the CCR with a free indication, in step 14, the charging-related resource obtained from the OCS (UE-T) in step 4 is returned to the OCS (UE-T), so as to achieve free processing for the destination user.

And step 15, sending the 200OK to the UE-T according to the IMS session establishment mode, and then carrying out other processes of the switching, including the notification of the switching result of the switching source UE-S and the switching initiator.

In this embodiment, if the destination user is an offline charging user, after step 13, the S-Anchor (UE-T) sends a charging request with a free indication to the CDF of the destination user according to the received free indication of the destination user, so that the CDF of the destination user includes the relevant information of the free indication in the generated CDR, thereby avoiding charging the destination user.

In this embodiment, if the source end user is an offline charging user, in step 12, the S-Anchor (UE-S) sends A Charging Request (ACR) to the CDF (UE-S) to request a new access leg, and the CDF (UE-S) generates a corresponding CDR according to the received request to charge for the switched multimedia session or media component. And simultaneously, the S-Anchor (UE-S) respectively sends ACR requests related to the old access leg and the far-end leg to the CDF (UE-S), the charging of the old access leg or the cut-out media component is stopped and the charging of the far-end leg is updated, and the CDF (UE-S) updates the corresponding charging data record according to the indication. If the charging is stopped for the old access leg, the ACR is used to stop the charging request, and other charging requests are updated. Here, if the new access leg, the old access leg and the remote leg are associated with the same charging session, the S-Anchor (UE-S) may send only one ACR update charging request to the CDF (UE-S), indicating to stop charging the old access leg or the switched-out media and update charging of the remote leg, and charging the new access leg. The processing of online charging in steps 5-7 and 9-11 may not be performed at this point.

In the above embodiment, if UE-S and UE-T are different modes of the same terminal, different terminals sharing an IP Multimedia Subsystem Public user identity (Share IMPU), different user identities of the same user, or data of two users of UE-S and UE-T may be shared, or S-Anchor (UE-S) and S-Anchor (UE-T) may also be the same entity, S-Anchor (UE-S) and S-Anchor (UE-T) may interact through an internal interface.

Both the first and second embodiments described above are directed to the case of an initial handover, i.e. a handover of a session or media component from UE-S to UE-T, and in the third embodiment, to the case of a handover from UE-T to UE-T2 again after a handover of a session or media component from UE-S to UE-T.

As shown in fig. 7, after the UE-S establishes a session with the UE-R through S-Anchor (UE-S) using SIP signaling or via CS network signaling, S1, S1 or S1, and the media component F1 contained in the session is switched to the UE-T, the present embodiment includes the following steps:

step 1, S-Anchor (UE-T) receives a handover request of a handover initiator, requests to cut in a cut-in session or media to UE-T2, wherein the handover initiator can be UE-S, UE-T, third party or HOCF or UE-T2, and sends the session or media to S-Anchor (UE-T) through SIP signaling or through CS network signaling.

And step 2, the S-Anchor (UE-T) performs switching control on the received switching request, and determines that the whole switched session or media component exists in the process and is free for the UE-T2 user according to the free indication obtained during initial switching, so that the UE-T2 user free indication is generated. And the S-Anchor (UE-T) executes free operation on the destination user according to the charging mode of the S-Anchor (UE-T) during the initial switching.

And 3-4, generating a free indication of the UE-T2 user in a session establishment request which takes a terminal identifier or a user identifier of the UE-T2 as a request URI by the S-Anchor (UE-T), routing the request to the S-Anchor (UE-T2) according to an IMS session establishment mode, and determining not to trigger online charging for the user of the online charging UE-T2 according to the free indication of the user of the UE-T2 after the service control is carried out on the S-Anchor (UE-T2).

Of course, similar to step 4 of the first embodiment, two other ways may be used to implement non-charging for the UE-T2 user.

And 5-8, the S-Anchor (UE-T2) routes the session establishment request to the UE-T2 according to an IMS session establishment mode, and the UE-T2 sends a session success establishment response 200OK to the S-Anchor (UE-T) through a switching intermediate process.

Step 9-13, the S-Anchor (UE-T) sends ReINVITE request (or UPDATE) to the UE-R to reach the S-Anchor (UE-S), after the S-Anchor (UE-S) performs service control, the S-Anchor (UE-S) sends CCR request to the OCS (UE-S), the OCS (UE-S) performs credit control according to the received request and returns corresponding response, and the response contains available resources.

Here, the CCR may be sent in the same charging session associated with the new, old and remote legs, and the S-Anchor (UE-S) sends a CCR update charging request to the OCS (UE-S) indicating that charging for the new access leg, the remote leg, is updated.

Here, CCR may also be associated with the access leg between S-Anchor (UE-S) and S-Anchor (UE-T). The S-Anchor (UE-S) additionally sends a CCR request to the OCS (UE-S) related to the remote leg indicating that charging of the remote leg is updated.

Step 14-21, S-Anchor (UE-S) sends the ReINVITE request to UE-R along the signaling path, and UE-R returns a 200OK response to S-Anchor (UE-S), optionally, S-Anchor (UE-S) sends a CCR request to OCS (UE-S) according to the process of message 9-13 to update available charging related resources, and OCS (UE-S) performs credit control according to the received request and returns a corresponding response, where the response includes the available resources.

After the above steps, other processes of switching are executed, including negotiation with the UE-T during source end processing and notification of switching results of the switching source end UE-T and the switching initiator. Throughout the process of handing off a new access leg established due to a handover of a handed off session or media to UE-T2 and existing after being handed off to UE-T2, the originating user charging system generates and maintains a complete charging history.

In the above embodiments, the UE-T, UE-T2 is taken as an IMS terminal for example. In the specific implementation process, if the UE-T, UE-T2 is a CS terminal, S-Anchor (UE-S) and UE-T, or S-Anchor (UE-T) establishes a new access leg with UE-T2, the MGCF used as the interface between IMS domain and CS domain in the signaling path established by the access leg, a free indication from S-Anchor (UE-S) or S-Anchor (UE-T) for the destination end user or UE-T2 user may be translated into a corresponding free indication for the CS domain, and transmitted to a CS domain, a CS domain charging initiation entity such as a VMSC or SCP of the destination user or UE-T2 user, interacting with the charging entity, and executing free operation of the destination end user or the UE-T2 user according to the indication, and including the related information of the free indication of the CS domain destination end user or the UE-T2 user in the charging record generated by the charging entity. When the destination user or the UE-T2 user charges online in the CS domain, the charging initiating entity in the CS domain can perform online charging for the destination user or the UE-T2 user according to the free indication corresponding to the CS domain. The charging initiating entity here is an entity which initiates a charging request to the online charging system, similar to the above-mentioned S-Anchor; of course, the S-Anchor sending the charging request to the charging system also belongs to the charging initiating entity.

The CS domain destination or UE-T2 user toll free indication may be a special number or a special indication, such as a prefix or a suffix added to the calling number or the called number, or a special service number.

In fig. 8, a charging flow including MGCF processing charging related information is described as an example of performing free control on a destination user in a CS domain, where the charging flow specifically includes the following steps:

step 1, UE-S has established a session with UE-R by S-Anchor (UE-S) using SIP signaling or via CS network signaling S1, S1 contains media component F1 and is anchored at S-Anchor (UE-S), S-Anchor (UE-S) receives a handover request of handover initiator, requesting to handover S1 or F1 to UE-T.

And 2-3, performing switching control on the received switching request by the S-Anchor (UE-S), detecting that the source end user is an offline charging user, and determining that the switching only charges the source end user, thereby generating a free indication of the destination end user. The generated session establishment request which takes the terminal identification (or user identification) of the UE-T as the request URI contains the free indication of the destination end user, and the session establishment request is routed to the MGCF according to the session establishment mode when the IMS and the CS are intercommunicated.

Step 4, MGCF converts the destination end user free indication into CS domain destination end user free indication according to destination end user free indication, the CS domain indication can be a special number or a special indication, for example, prefix or suffix is added in calling number or called number; or use a special service number to indicate that the CS domain destination is free, etc., and include this indication in an Initial Address Message (IAM) directed to the CS network serving the destination.

And 5-6, the CS network executes free processing to the destination user according to the free indication in the IAM.

Step 7-11, the CS network routes the setup (setup) message to the UE-T (CS), the UE-T routes the connection message (connect) to the CS network through the intermediate negotiation process between the S-Anchor (UE-S) and the UE-T (CS), the CS network converts the response message (ANM) into a response message (ANM) and sends the response message (ANM) to the MGCF, and the MGCF converts the response message (ANM) into 200OK to route the message to the S-Anchor (UE-S).

Step 12-14, S-Anchor (UE-S) sends ACR start charging request to CDF (UE-S), CDF (UE-S) generates corresponding CDR according to the received request. Simultaneously, CDF (UE-S) respectively sends ACR requests related to the old access leg and the far-end leg, and indicates to stop charging the old access leg or cut-out media and update the charging of the far-end leg; if the charging is stopped for the old access leg, the ACR is used to stop the charging request, and other charging requests are updated.

Here, if the same charging session is associated with the new, old and remote legs, the S-Anchor (UE-S) sends an ACR update charging request to the CDF (UE-S) indicating to stop charging the old access leg or the cut-out media and update charging of the remote leg, and to charge the new access leg.

And step 15, processing other processes of switching, including negotiation with the UE-R, negotiation with the UE-S during source processing, and notification of switching results of the switching source UE-S and the switching initiator. Wherein, according to the initial establishing direction of the switching session (whether the UE-S is a calling party or a called party) or the initial initiating direction of the switched media, the S-Anchor (UE-S) can charge according to the direction.

In the first, second, and third embodiments, the destination user or the UE-T2 user is used as an online charging user for description, and if the destination user or the UE-T2 user is an offline charging user, the UE-T or UE-T2 side network entity may carry the relevant information of the free indication of the destination user or the UE-T2 user in the ACR request sent to the CDF (UE-T) or the CDF (UE-T2) according to the free indication of the destination user or the UE-T2 user in the session establishment request or the session establishment response, so that the CDR generated by the CDF (UE-T) or the CDF (UE-T2) includes the relevant information of the free indication. The related information freely indicated by the destination user or the UE-T2 user can be carried in the Service specific Data or the Service-Context-Id AVP in the ACR request.

In the above flow, the free indication carried in the session establishment request or response may be carried by an SIP-Charging-Vector header field, may be carried by a newly defined SIP header field or parameter, may be carried by an extension using an original header field or parameter, or may be carried by message content of SDP.

The above three embodiments are all applicable to the case of charging the source end user in the handover process, and the case of charging the destination end user in the handover process is described through the three embodiments below.

The flow of the fourth embodiment of the method of the present invention is shown in fig. 9, and comprises a media component F1 in S1, S1 when a UE-S has established a session with UE-R using SIP signaling or via CS network signaling via S-Anchor (UE-S), and thereafter, the following steps are included:

step 1, S-Anchor (UE-S) receives a handover request of a handover initiator, requests to handover S1 or F1 to UE-T, wherein the handover initiator can be UE-S, UE-T, a third party or HOCF, and is sent to S-Anchor (UE-S) through SIP signaling or via CS network signaling.

And 2-3, the S-Anchor (UE-S) performs switching control on the received switching request, determines that a new access leg only charges a destination terminal user, generates a session establishment request taking a terminal identifier or a user identifier of the UE-T as a request URI, and routes the request to the S-Anchor (UE-T) according to an IMS session establishment mode.

And 4-7, judging that the received session establishment request is a request for establishing a new access leg for the switched multimedia service by the S-Anchor (UE-T), after service control is carried out, sending a CCR request to the OCS (UE-T) aiming at the new access leg, carrying out credit control on the OCS (UE-T) and returning a corresponding response, wherein the response comprises available resources.

And 8-10, the S-Anchor (UE-T) routes the session establishment request to the UE-T according to an IMS session establishment mode, and through an intermediate negotiation process between the S-Anchor (UE-S) and the UE-T, the UE-T routes a session establishment success response 200OK sent to the S-Anchor (UE-S) to the S-Anchor (UE-T) according to the IMS session establishment mode to complete establishment of a new access leg between the S-Anchor (UE-S) and the UE-T.

Step 11-14, the S-Anchor (UE-T) sends a CCR request to the OCS (UE-T) to update available resources, the OCS (UE-T) performs credit control and returns a corresponding response, the response comprises the available resources, the S-Anchor (UE-T) forwards the 200OK to the S-Anchor (UE-S), and the online charging of a new access leg to a destination end user is realized through the steps.

Step 15-18, S-Anchor (UE-S) sends ACR request to CDF (UE-S), where the ACR request includes free indication for new access leg, CDF (UE-S) generates corresponding CDR including related information of the free indication according to the received request, and CDF (UE-S) returns response of ACR request. At this time, if the same charging session is associated with the new, old and remote legs, the ACR update charging request sent by the S-Anchor (UE-S) to the CDF (UE-S) further indicates to stop charging the old access leg or the cut-out media and update charging of the remote leg, and to free the new access leg.

The new access leg can be used for free of the source end user, the ACR causes a charging session to be established, and the CDF (UE-S) generates a corresponding CDR containing the free indication related information according to the received request. And when renegotiating with UE-R, negotiating with UE-S when processing the source end, S-Anchor (UE-S) sends ACR request related to old access leg and far-end leg to CDF (UE-S) respectively, indicating to stop charging old access leg or cut-out media and updating charging of far-end leg; if the charging is stopped for the old access leg, the ACR is used to stop the charging request, and other charging requests are updated.

The above describes how to realize free charging for the source end user by taking the source end user as an offline charging user as an example. In a specific implementation, if a source end user is an online charging user, in step 3, an S-Anchor (UE-S) sends a CCR request to an OCS (UE-S), wherein the request contains information free of charge of the source end user, and the OCS (UE-S) executes the operation free of charge of the source end user according to the information; or, the S-Anchor (UE-S) sends a CCR request to an OCS (UE-S), the OCS (UE-S) executes normal credit control, and the S-Anchor (UE-S) returns all applied resources to the OCS (UE-S) when the communication is finished; or, the S-Anchor (UE-S) does not interact with the OCS (UE-S) for the new access leg, and performs free operation on the source end user, and at this time, the offline charging process in step 15-18 may not be executed any more. At this time, if the same charging session is associated with the new, old and remote legs, the CCR sent by the S-Anchor (UE-S) to the OCS (UE-S) further includes information indicating that charging for the old access leg or the switched-out media is stopped and information updating charging for the remote leg, and information for free for the new access leg. If the new, old and remote legs are not associated to the same charging session, the CCR results in a charging session being established, and the OCS (UE-S) generates a charging record containing the free indication for the source subscriber for the new access leg based on the received request. When renegotiating with UE-R and negotiating with UE-S when processing source end, S-Anchor (UE-S) sends CCR requests related to old access leg and far-end leg to OCS (UE-S) respectively, and indicates to stop charging the old access leg or cut-out media and update charging of the far-end leg; if the charging is stopped for the old access leg, the charging request is stopped by using the CCR, and other charging requests are updated. When three charging sessions are associated with the new, old and remote legs, and when the S-Anchor (UE-S) detects that only the destination subscriber is charged and the source subscriber is an online charging subscriber, it may also process the new access leg as follows:

the method comprises the steps that S-Anchor (UE-S) sends a CCR request to OCS (UE-S), the OCS (UE-S) executes normal credit control, and when a new access leg is released, the S-Anchor (UE-S) returns all applied resources to the OCS (UE-S), so that the new access leg can carry out free charge on a source end user; or the S-Anchor (UE-S) does not perform charging information interaction on the new access leg with the OCS (UE-S), so that the source end user can be operated freely by the new access leg.

At the end of fig. 9, the processing of other procedures for handover includes notification of the handover results of the handover source UE-S and the handover initiator. Furthermore, the destination subscriber billing system generates and maintains a complete billing history during the handed-over session or media is handed-over to the UE-T and throughout the period that exists after being handed-over to the UE-T.

In this embodiment, both the ACR and the CCR sent by the S-Anchor (UE-S) may include an associated charging identifier, where the identifier may be a globally unique identifier or a local identifier, and charging records generated by the CDF (UE-S) or the OCS (UE-S) include the associated charging identifier, so that charging records of a new access leg, an old access leg, and a remote leg for a source end user may be associated through the identifier. In addition, in the process of establishing a new access leg caused by handover, the S-Anchor (UE-S) may further include the associated charging identifier in a session establishment request or response sent to the UE-T network side, and through interaction between the UE-T side charging initiation entity and the CDF (UE-T) or OCS (UE-T), the CDF (UE-T) or OCS (UE-T) on the UE-T side also includes the associated charging identifier in a charging record generated for the destination end user by the CDF (UE-T) or OCS (UE-T), and the CDF (UE-T) or OCS (UE-T) includes information related to the identifier in the charging record generated for the destination end user in the whole life process of the switched session or media component. Therefore, the related charging records in different charging systems for the switched multimedia service can be all related through the related charging identification.

In addition, in this embodiment, the S-Anchor (UE-S) may further include a session initial establishment direction of handover or an initial initiation direction of a media component in a session establishment request or response sent to the UE-T network side, and the charging initiation entity of the UE-T network side may include the initial direction of the session or the media component of handover in a charging request sent to the CDF (UE-T) or the OCS (UE-T), so that the CDF (UE-T) or the OCS (UE-T) may charge the new access leg according to the initial direction.

In the above flow, the associated Charging identifier, the initial establishment direction, or the initial initiation direction before the handover of the switched media component, which are carried in the session establishment request or response, may be carried by an SIP-Charging-Vector header, may be carried by newly defining an SIP header or parameter, may be carried by using an original header or parameter for extension, or may be carried by the message content of SDP.

The flow of the fifth embodiment of the method of the present invention is shown in fig. 10, where the UE-S has established a session S1 with UE-R using SIP signaling or via CS network signaling through S-Anchor (UE-S), S1 contains a media component F1, and thereafter, comprises the following steps:

step 1-5, UE-T initiates a switching request in a session establishment mode according to user indication, preset strategy or receiving a switching request of UE-S, a third party or an HOCF, and requests to switch S1 or F1 to the UE-T. The request reaches S-Anchor (UE-T) along a session establishment path, the S-Anchor (UE-T) executes relevant service control, a CCR request is sent to OCS (UE-T), the OCS (UE-T) returns a corresponding response after credit control, and the response comprises available charging relevant resources.

In step 6, the S-Anchor (UE-T) sends a session establishment request to establish a new access leg, which is routed to the S-Anchor (UE-S) in an IMS session establishment mode. Then, in step 7-10, the S-Anchor (UE-S) performs handover control according to the received session establishment request, and determines that the charging object is the destination subscriber, the S-Anchor (UE-S) sends a CCR request to the OCS (UE-S), where the request includes information indicating that the new access leg is free, and the OCS (UE-S) performs free operation for the source subscriber according to the information, and returns a corresponding response.

At this time, if the same charging session is associated with the new, old and remote legs, the CCR sent by the S-Anchor (UE-S) to the OCS (UE-S) further includes information indicating that charging for the old access leg or the switched-out media is stopped and information updating charging for the remote leg, and information for free for the new access leg.

If the new, old and remote legs are not associated to the same charging session, the CCR results in a charging session being established, and the OCS (UE-S) generates a charging record containing the free indication for the source subscriber for the new access leg based on the received request. When renegotiating with UE-R and negotiating with UE-S when processing source end, S-Anchor (UE-S) sends CCR requests related to old access leg and far-end leg to OCS (UE-S) respectively, and indicates to stop charging the old access leg or cut-out media and update charging of the far-end leg; if the charging is stopped for the old access leg, using the CCR to stop the charging request, and adopting an updating charging request for the other access legs; or for the new access leg, the S-Anchor (UE-S) does not send the CCR to the OCS (UE-S), thereby realizing free.

In step 8-10, when three charging sessions are associated with the new, old and remote legs, and the S-Anchor (UE-S) detects that only the destination subscriber is charged and the source subscriber is an online charging subscriber, the process may also be performed for the new access leg:

In step 11-14, after the handover intermediate procedure, the S-Anchor (UE-S) sends a CCR request to the OCS (UE-S), optionally performed according to a similar procedure in step 7-10.

In step 15-18, the S-Anchor (UE-S) sends a session success establishment response 200OK request to the UE-T, the S-Anchor (UE-T) executes the relevant service control, sends a CCR request to the OCS (UE-T), and the OCS (UE-T) returns a corresponding response after performing credit control, where the response includes the available charging relevant resources.

Then, in step 19, S-Anchor (UE-T) routes the 200OK to UE-T in IMS session setup. Then, in step 20, other procedures of handover are performed, including negotiation with the UE-R, negotiation with the UE-S during source processing, and notification of handover results of the source UE-S and the handover initiator. Furthermore, the destination end-user charging system generates and maintains a complete charging history during the switched session or media being switched to the UE-T, and throughout the period of time that exists after being switched to the UE-T.

The above describes how to realize free charging for the source end user by taking the source end user as an online charging user as an example. In a specific implementation, if the source end user is an offline charging user, in step 15, the S-Anchor (UE-S) sends an ACR request to the CDF (UE-S), where the request includes information free of charge of the source end user, the CDF (UE-S) generates a corresponding CDR including the information related to the free indication according to the received request, and the CDF (UE-S) returns a response to the ACR request. At this time, if the same charging session is associated with the new, old and remote legs, the ACR update charging request sent by the S-Anchor (UE-S) to the CDF (UE-S) further indicates to stop charging the old access leg or the cut-out media and update charging of the remote leg, and to free the new access leg. The new access leg can be used for free of the source end user, the ACR causes a charging session to be established, and the CDF (UE-S) generates a corresponding CDR containing the free indication related information according to the received request. And when renegotiating with UE-R, negotiating with UE-S when processing the source end, S-Anchor (UE-S) sends ACR request related to old access leg and far-end leg to CDF (UE-S) respectively, indicating to stop charging old access leg or cut-out media and updating charging of far-end leg; if the charging is stopped for the old access leg, the ACR is used to stop the charging request, and other charging requests are updated. The processing of online charging in steps 8-10 and 12-14 may not be performed at this point.

In the fourth and fifth embodiments that only the destination user is charged, the destination user is taken as an online charging user for example. In the specific implementation process, if the destination user is an offline charging user, when the UE-T side network entity receives the 200OK response from the new access leg, it may send an ACR request to the CDF (UE-T) and generate a corresponding CDR at the CDF (UE-T), so as to perform charging control on the destination user.

In addition, in the fourth and fifth embodiments, UE-T is taken as an IMS terminal as an example. In the specific implementation process, if UE-T is a CS terminal, during the process of establishing a new access leg between S-Anchor (UE-S) and UE-T2, MGCF may convert the initial establishment direction and/or initial initiation direction and associated charging identifier, which are transmitted from S-Anchor (UE-S) to the UE-T side network, into a CS domain corresponding indication, and transmit the CS domain corresponding indication to the CS domain, and a CS domain charging initiation entity of a destination user, such as VMSC or SCP, interacts with the CS domain charging system, charges the destination user according to the information and includes the associated charging identifier in the generated charging record.

The indication corresponding to the associated charging identifier in the CS domain may be a special number or a special indication, such as a prefix or a suffix added to the calling number or the called number, or may be a special service number.

In the flow of the sixth embodiment of the method of the present invention as shown in fig. 11, first, the UE-S has established a session with the UE-R through S-Anchor (UE-S) using SIP signaling or via CS network signaling, the media component F1 contained in S1, S1 or S1 has been handed over to the UE-T, and thereafter, the embodiment comprises the following steps:

step 1, S-Anchor (UE-T) receives a handover request of a handover initiator, requests to cut in a cut-in session or media to UE-T2, wherein the handover initiator can be UE-T, a third party or HOCF or UE-T2, and sends the session or media to S-Anchor (UE-T) through SIP signaling or through CS network signaling.

And step 2, the S-Anchor (UE-T) performs switching control on the received switching request, and determines to charge only the UE-T2 user according to the charging strategy, and then the S-Anchor (UE-T) executes free operation on the destination user according to the charging mode of the S-Anchor (UE-S) during initial switching.

In step 3-7, the S-Anchor (UE-T) generates a session establishment request with the terminal identifier or the user identifier of the UE-T2 as a request URI, the session establishment request is routed to the S-Anchor (UE-T2) according to an IMS session establishment mode, the S-Anchor (UE-T2) performs service control according to the request, and after judging that the UE-T2 user is an online charging user, the S-Anchor (UE-T2) sends a CCR request to an OCS (UE-T2), the OCS (UE-T2) performs credit control and returns a corresponding response, and the response comprises available resources.

In step 8-10, the S-Anchor (UE-T2) routes the session establishment request to the UE-T2 in an IMS session establishment mode, and through an intermediate negotiation process between the S-Anchor (UE-T) and the UE-T, the UE-T2 routes the 200OK sent to the S-Anchor (UE-S) to the S-Anchor (UE-T2) in an IMS session establishment mode.

After receiving the session establishment success response 200OK in step 11-14, the S-Anchor (UE-T2), optionally sending a CCR request to the OCS (UE-T2), where the OCS (UE-T2) performs credit control and returns a corresponding response, where the response includes available resources, and the S-Anchor (UE-T2) routes the session establishment success response to the S-Anchor (UE-T) according to the IMS session establishment manner.

In step 15-27, the S-Anchor (UE-T) performs other procedures for handover, including negotiation with the UE-R, negotiation with the UE-T during source processing, and notification of handover results of the handover source UE-T and the handover initiator. In the negotiation process with the UE-R, the S-Anchor (UE-S) carries out charging processing according to the initial switching mode, namely the source end user is free.

Furthermore, the UE-T2 user charging system generates and maintains a complete charging history during the time that the handed-over session or media is handed-over again to UE-T2, and throughout the time that it exists after being handed-over to UE-T2.

In this embodiment, a UE-T2 user is taken as an example of an online charging user. In practical applications, the UE-T2 user goes offline, and N2C and all subsequent handovers can be subject to charging control in a similar manner as the initial handover.

In a seventh embodiment of the invention, the case is addressed where the session and media components are switched from UE-S to UE-T and then back to UE-S again. In this case, when the handover initiator initiates a handover to S-Anchor (UE-S) and requests to switch back a session and a media component from UE-T to UE-S, the S-Anchor determines that the session or the media component that has been switched back is to be switched back, and then the handover is referred to as a second handover, and determines that a new access leg established in the second handover only charges a source end user, and then during the handover or after the handover is successful, a step similar to the charging control for the source end user in the first embodiment or the second embodiment is performed, so as to perform charging control for the source end user.

In the foregoing embodiments, whether the charging system is an originating user, a destination user, or a UE-T2 user, a charging request or a charging response sent by an entity interacting with charging information may include the same associated charging identifier related to the switched multimedia service, and all charging records generated by the charging system and related to the multimedia service include the associated charging identifier. Before the handover, the charging request or the charging response sent by the S-Anchor (UE-S) to the charging system of the source end user also includes the associated charging identifier, so that all charging records associated with the multimedia service, generated by different charging systems at different times, are associated by the associated charging identifier.

The foregoing is a description of specific embodiments of the invention, and the method of the invention may be modified, as appropriate, during the course of particular implementations to suit the particular needs of particular situations. It is therefore to be understood that the particular embodiments in accordance with the invention are illustrative only and are not intended to limit the scope of the invention.

Claims

1. A charging method for multimedia service continuity is characterized in that the method comprises the following steps:

determining a charging object;

the new access leg is established in the multimedia service switching.

2. The method of claim 1, wherein determining the charging object comprises:

and determining the charging object as a source end user or a destination end user according to the operator strategy.

3. The method of claim 1, wherein the new access leg established in the handover is: signaling connection between a session control signaling plane Anchor point S-Anchor (UE-S) and a UE-T at a UE-S network side;

if the multimedia service is switched into a new session, the signaling connection is the session signaling connection of the new session;

if the multimedia service is switched into the existing session, the signaling connection is established in the session signaling connection of the existing session, and associates and controls the signaling connection of the media component switched into the existing session.

4. The method of claim 1, wherein the network performing charging control on the new access leg on the UE-S side comprises:

and the Anchor point S-Anchor (UE-S) of the session control signaling plane of the UE-S network side sends a charging request to a charging data function entity CDF (UE-S) of the source end user, and the CDF (UE-S) generates charging information including the new access leg in a charging data record CDR for the source end user according to the charging request.

5. The method of claim 4, wherein the charging request sent by the S-Anchor (UE-S) to the CDF (UE-S) comprises: requesting information for starting charging for a new access leg established between the S-Anchor (UE-S) and the UE-T for the multimedia service;

the network performing charging control on the new access leg at the UE-S side further comprises: the S-Anchor (UE-S) sends two charging requests to the CDF (UE-S), wherein one charging request is used for requesting the information for stopping charging for an old access leg established between the S-Anchor (UE-S) and the UE-S by the multimedia service; and the other charging request is used for requesting information for updating charging of a remote leg established between the S-Anchor (UE-S) and a remote UE-R for the multimedia service.

6. The method of claim 4, wherein the charging request sent by the S-Anchor (UE-S) to the CDF (UE-S) comprises: requesting information for starting charging for a new access leg established between the S-Anchor (UE-S) and the UE-T for the multimedia service, requesting information for updating charging for a remote leg between the S-Anchor (UE-S) and a remote UE-R for the multimedia service, and requesting information for stopping charging for an old access leg established between the S-Anchor (UE-S) and the UE-S for the multimedia service.

7. The method of claim 1, wherein the network performing charging control on the new access leg on the UE-S side comprises:

and a session control signaling plane Anchor point S-Anchor (UE-S) at the UE-S network side sends a credit control request to an online charging system OCS (UE-S) of the UE-S, and the OCS (UE-S) generates information for charging the new access leg in a charging record.

8. The method of claim 7, wherein the credit control request sent by the S-Anchor (UE-S) to the OCS (UE-S) comprises: requesting information for starting charging for a new access leg established between the S-Anchor (UE-S) and the UE-T for the multimedia service;

the network performing charging control on the new access leg at the UE-S side further comprises:

the S-Anchor (UE-S) additionally sends two credit control requests to the OCS (UE-S), and one credit control request requests the information that the charging of an old access leg established by the multimedia service between the S-Anchor (UE-S) and the UE-S is stopped; another credit control request requests information for updating charging of a remote leg established by the multimedia service between the S-Anchor (UE-S) and a remote UE-R.

9. The method of claim 7, wherein the credit control request sent by the S-Anchor (UE-S) to the OCS (UE-S) comprises: requesting information for starting charging for a new access leg established between the S-Anchor (UE-S) and the UE-T for the multimedia service, requesting information for updating charging for a remote leg between the S-Anchor (UE-S) and a remote UE-R for the multimedia service, and requesting information for stopping charging for an old access leg established between the S-Anchor (UE-S) and the UE-S for the multimedia service.

10. The method according to any of claims 4 to 6, wherein the charging request sent by the S-Anchor (UE-S) to the CDF (UE-S) includes charging associated information, and the CDF (UE-S) includes the charging associated information in the generated charging record.

11. The method of claim 10, wherein the charging correlation information is a session identifier of the same charging session established by the CDF (UE-S) for the source subscriber, or a special charging identifier associated with a new access leg, an old access leg, and a remote leg.

12. The method according to any of claims 7 to 9, wherein the charging request sent by the S-Anchor (UE-S) to an OCS (UE-S) includes charging correlation information, and the OCS (UE-S) includes the charging correlation information in the generated charging record.

13. The method of claim 12, wherein the charging correlation information is a session identifier of the same charging session established by the OCS (UE-S) for the source subscriber, or a special charging identifier associated with a new access leg, an old access leg, and a remote leg.

14. The method of claim 1, wherein sending an indication to a UE-T side network free of charge for the new access leg is: and carrying a free indication for the new access leg to the destination user for free in a session establishment request sent to the UE-T side network or a response returned according to the received session establishment request from the UE-T side network by a session control signaling plane Anchor point S-Anchor (UE-S) at the UE-S network side.

15. The method according to claim 14, wherein the free indication is carried in the session establishment request or response by a session initiation protocol P Charging Vector SIP P-Charging-Vector header field of the session establishment request or response, or by newly defining a SIP header field or parameter carrier, or by using a header field or parameter other than an original SIP P-Charging-Vector for extension carrier, or by message content of a Session Description Protocol (SDP).

16. The method of claim 1, wherein the UE-T is a CS terminal; the UE-T side network receiving the indication comprises:

and the media gateway control entity MGCF interfaced with the UE-T side network converts the free indication into a free indication of the CS domain and sends the free indication to a charging initiating entity of the CS domain.

17. The method of claim 1, wherein the UE-T is an IMS terminal; the UE-T side network receiving the free indication comprises:

and the charging initiation entity in the UE-T side network receives the free indication.

18. The method according to claim 16 or 17, wherein the UE-T side network receives a free indication and the free control of the new access leg comprises:

after receiving the free indication, a charging initiation entity in the UE-T side network sends a charging request with the free indication to a charging data function entity CDF (UE-T) of the destination user; the CDF (UE-T) sets the free indication in the CDR generated according to the charging request.

19. The method according to claim 16 or 17, wherein the UE-T side network receives a free indication and the free control of the new access leg comprises:

after receiving the free indication, a charging initiation entity in the UE-T side network sends a credit control request with the free indication to an online charging system OCS (UE-T) of the destination end user, and the OCS (UE-T) sets the free indication in a charging record generated for the destination end user according to the credit control request; or after receiving the free indication, returning the charging related resources acquired from the OCS (UE-T) before; or after receiving the free indication, the charging initiation entity in the UE-T side network does not interact with an OCS (UE-T) to control the UE-T free.

20. The method of claim 1, wherein after performing charging control based on the determined charging object, the method further comprises:

receiving a switching request for switching the multimedia service to a second destination terminal UE-T2;

performing charging control on the source end user on the UE-S network side according to the new access leg switched to the UE-T2;

sending an indication to a UE-T2 side network free of charge for the switching to the new access leg of UE-T2;

the UE-T2 side network receives the indication and takes free control of the new access leg switched to UE-T2.

21. The method of claim 1, wherein the network controlling the new access leg for free at the UE-S side comprises:

and the Anchor point S-Anchor (UE-S) of the session control signaling plane of the UE-S network side sends a charging request comprising a free indication to a charging data function entity CDF (UE-S) of the UE-S, and the CDF (UE-S) sets the free indication in a charging data record CDR aiming at the new access leg for a source end user according to the charging request.

22. The method of claim 21, wherein the network controlling the new access leg for free at the UE-S side further comprises:

the S-Anchor (UE-S) sends two charging requests to the CDF (UE-S), wherein one charging request is used for requesting charging information for stopping charging for an old access leg established between the S-Anchor (UE-S) and the UE-S by the multimedia service; and the other charging request is used for requesting information for updating charging of a remote leg established between the S-Anchor (UE-S) and a remote UE-R for the multimedia service.

23. The method of claim 21, wherein the charging request sent by the S-Anchor (UE-S) to the CDF (UE-S) further comprises: requesting for updating charging information of a far-end leg of the multimedia service between the S-Anchor (UE-S) and a far-end UE-R, and requesting for stopping charging information of an old access leg established between the S-Anchor (UE-S) and the UE-S.

24. The method of claim 1, wherein the network controlling the new access leg for free at the UE-S side comprises:

a session control signaling plane Anchor point S-Anchor (UE-S) at the UE-S network side does not send a credit control request to an OCS (UE-S) of the UE-S;

or the S-Anchor (UE-S) sends a credit control request comprising a free indication to an OCS (UE-S), and the OCS (UE-S) performs free operation for the source user aiming at the new access leg;

or, after the S-Anchor (UE-S) sends the credit control request to the OCS (UE-S) to acquire the charging related resource, the acquired charging related resource is returned to the OCS (UE-S).

25. The method of claim 24, wherein the network controlling the new access leg for free at the UE-S side further comprises:

26. The method of claim 24, wherein the sending of the credit control request by the S-Anchor (UE-S) to the OCS (UE-S) further comprises: requesting for updating charging information of a far-end leg of the multimedia service between the S-Anchor (UE-S) and a far-end UE-R, and requesting for stopping charging information of an old access leg established between the S-Anchor (UE-S) and the UE-S.

27. The method of claim 21, wherein the charging request sent by the S-Anchor (UE-S) includes an associated charging identifier, and the CDF (UE-S) associates the charging records of the new access leg, the old access leg, and the remote leg according to the received associated charging identifier.

28. The method of claim 24, wherein the credit control request sent by the S-Anchor (UE-S) includes an associated charging identifier, and wherein the OCS (UE-S) associates the charging records of the new access leg, the old access leg, and the remote leg according to the received associated charging identifier.

29. The method of claim 1, wherein the UE-T network performing charging control on the new access leg comprises:

a charging initiating entity in the UE-T side network sends a charging request aiming at the new access leg to a charging data function entity CDF (UE-T) of the destination terminal user; and the CDF (UE-T) generates a corresponding CDR according to the charging request to charge the destination terminal user.

30. The method of claim 1, wherein the UE-T network performing charging control on the new access leg comprises:

and a charging initiating entity in the UE-T side network sends a credit control request to an online charging system OCS (UE-T) of the destination terminal user, and the OCS (UE-T) generates information for charging the new access leg in a charging record.

31. The method of claim 1, wherein a session control signaling plane Anchor S-Anchor (UE-S) on the UE-S network side sets the initial direction of the switched multimedia service in a session establishment request sent to the UE-T network side or in a response returned according to the session establishment request from the UE-T network side; the UE-T network side carries out charging control to the destination end user according to the initial direction of the switched multimedia service.

32. The method of claim 1, wherein a session control signaling plane Anchor S-Anchor (UE-S) on the UE-S network side includes an associated charging identifier in a session establishment request sent to the UE-T network side or in a response returned according to the session establishment request from the UE-T network side;

after receiving the associated charging identifier, the UE-T network side includes the associated charging identifier in the charging record generated for the destination user.

33. The method according to claim 31, wherein the initial direction is carried in the session establishment request or response by a session initiation protocol P Charging Vector SIP P-Charging-Vector header field of the session establishment request or response, or by newly defining a SIP header field or parameter carrier, or by using a header field or parameter other than an original SIP P-Charging-Vector for extension carrier, or by message content carrier of a Session Description Protocol (SDP).

34. The method of claim 33, wherein the UE-T is a CS terminal; the UE-T side network receiving the initial direction comprises:

MGCF of the UE-T side network interface correspondingly converts the initial direction into the initial direction of the CS domain and sends the initial direction to the charging initiation entity of the destination user in the CS domain.

35. The method according to claim 32, wherein the associated Charging identifier is carried in the session establishment request or response by a session initiation protocol P Charging Vector SIP P-Charging-Vector header field of the session establishment request or response, or by newly defining an SIP header field or parameter carrier, or by using a header field or parameter other than an original SIP P-Charging-Vector for extension carrier, or by message content of a Session Description Protocol (SDP).

36. The method of claim 35, wherein the UE-T is a CS terminal; the UE-T side network receiving the associated charging identifier comprises:

and the MGCF of the UE-T side network interface correspondingly converts the associated charging identifier into an associated charging identifier of the CS domain and sends the associated charging identifier to a charging initiating entity of the destination user in the CS domain.

37. The method of claim 1, wherein after performing charging control based on the determined charging object, the method further comprises:

performing charging control on the UE-T2 user on the UE-T2 network side for the new access leg switched to the UE-T2;

and performing free control on the new access leg switched to the UE-T2 at the UE-S network side and the UE-T network side.

38. The method of claim 1, wherein after receiving the handover request, further comprising:

a session control signaling plane Anchor point S-Anchor (UE-S) at a UE-S network side sends an event type charging request to a charging data function entity CDF (UE-S) of a source end user, and the CDF (UE-S) generates a corresponding CDR for charging aiming at the switching event according to the charging request and then returns a charging response; or,

and the S-Anchor (UE-S) sends an event type credit control request to an OCS (UE-S) of the UE-S, and the OCS (UE-S) returns a corresponding response after performing credit control for charging aiming at the switching event according to the credit control request.

39. The method of claim 1, wherein during the handover, a session control signaling plane Anchor S-Anchor (UE-S) serving the UE-S is in a same entity as a session control signaling plane Anchor S-Anchor (UE-T) serving the UE-T;

the UE-S and the UE-T are as follows: different modes of the same terminal of the same user in the same network, different terminals of different users in the same network, or different terminals in different networks.

40. The method of claim 39, wherein the terminal is an IMS terminal or a CS terminal.

41. A session control signaling plane anchor, comprising: